Poki, being the game's creator, has had a couple of roles in the story. The most prevalent is as the bard. He appears at the beginning of each new chapter and sings a verse of Rufus' tale in Deponia
As the bard, he wears a black t-shirt, blue pants, toeless boots a belt with a side pouch and a nifty top hat, constructed from a small tyre, an opened tin, a spoon and what the author of this page can only describe as "a pair of brass eyelash curlers, or something".
He is also rocking a guitar/lute, also most likely constructed from junk.
Being a bard, he sings quite humourous tales of Rufus' journey. In between each chapter, he sums up the recent events and gives a hint to what is around the corner in a verse.
He often inserts double entendres into his lyrics and often sums up with a joke in his last line.
Sometimes his lyrics break the fourth wall and uses chorus of singers that echo his last line as a comedic tool.